Abstract: Based on the result of the interpretation of remote sensing,the desert in Qinghai province can be diveded into two types of formation, fifteen types of shape and three types of activity. After measuring the areas of every type in every county and prefecture this paper expounds the characteristic of shape, distributed laws and desertified environment respectively. From three aspects of geological history,sand source and climate,the natural factors of formation and development of desert were analysed. Through comparing remote sensing image of different time the paper reveals the effects of natural man-made factors on desertified environment and points out its developping tendency:1. The uplift of Qinghai-Tibetan plateau will have a bad influence on the fragile ecological environment in desert area. 2. The tendency of climate beconming dry and dry has been continuing. 3. The effect of human activity on environment is becoming apparent day by day. 4. Desertification will intensify.